Tools that accept the distal end of a strap of a fastener projecting from the locking head of the fastener, grip the strap and draw the strap away from the head of the fastener to tighten the fastener around an object, are well known. See U.S. Pat. No. 3,661,187 owned by our common assignee, Panduit Corp. which discloses one such tool. This type of tool includes a mechanism that senses the tension applied to the fastener and severs the strap adjacent the head at a preset tension level.
This type of tool is utilized to apply metal ball-lock ties of the type described in U.S. Pat. No. 4,399,592, which patent is owned by our common assignee, Panduit Corp. The locking mechanism of the metal ball-lock tie includes a metal ball contained within the head of the tie that moves along the length of the strap of the tie from a first position that does not interfere with the insertion and tensioning of the strap to a second position that wedges the metal ball against the strap and the head of the tie to lock the strap to the head. This movement of the ball results in a limited release of the preset tension induced in the strap by an application tool.
In numerous applications the small release of the preset tension in the fastener is not great enough to affect the operation of the metal ties, or is offset by the resiliency of the objects being bundled.
In certain applications, for example, where the object around which the metal tie is fastened is a non-resilient metal column, the release of a portion of the preset tension induced in the tie by an application tool results in a loosely applied metal tie.